Download B.Ladder Programming algorithm

International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012
PLC Based Automatic Control of Rheometer
Khin Su Hlaing1, Kyaw Zin Latt2

Abstract— This paper describes the automatic control of
rheometer. Rheometer is a quality control instrument that is
used in rubber-related manufacturing industries. Rheometer
can measure viscosity and viscoelasticity of fluids, semi-solids
and solids. The operation of rheometer is fully controlled by
using Programmable Logic Controllers (PLC’S) which acts the
heart of the system. The system sequence of operation is
designed by ladder diagram and the plc programming software.
Sensor usually plays its vital part as an input signal transmitter
for the plc in the system. By programming the PLC we control
the entire system. During this project, sensor has been used to
sense the temperature and to control the DC motor. The input
signal that has been sent from the sensor to the plc has being
made as a reference. Signal in order to determine the output
signal that exactly a same with the plc programming language
based on the user requirement. The entire system is more
flexible and time saving. This developed apparatus is useful not
only for testing purpose, but it can be used for research for
other types of materials also.
Index Terms— Rheometer, PLC, Ladder Diagram, Sensor, DC
Motor
four major components: PLC controller, DC motor driver,
LM35 sensor and IR sensor. LM35 sensor is used to know the
temperature and IR sensor is used to control the DC motor. If
the 24Vdc is supplied to the PLC input, the output of PLC
shows the “ON” state of heater the shutter is closed.IR sensor
is used to stop the shutter motor. And then the torque motor
starts forward direction to press the sample. If the
temperature sensor gets the required temperature, the output
of the PLC shows “OFF” state of the heater and torque motor
stops. And then the shutter motor and torque motor start
reverse direction. IR sensor is used to stop the motor. Figure
1 shows the overall block diagram of the system.
Torque Motor
DC Motor
Drive Circuit
Programmable
Logic
Controller
Shutter Motor
DC Motor
Drive Circuit
I. INTRODUCTION
Rheometer is a quality control instrument that is used in
rubber-related manufacturing industries. The rheometer is
used to measure the viscosity of the rubber. The measurement
of viscosity must be done in presence of temperature. Today,
rubber is finding a wide variety of applications from daily
usage to the industrial applications. The field of automation
has had a notable impact in a wide range of industries beyond
manufacturing. Automation is the use of control systems and
information technologies to reduce the need for human work
in the production of goods and services. In the scope of
industrialization, automation is a step beyond mechanization.
Whereas mechanization provides human operators with
machinery to assist them with the muscular requirements of
work, automation greatly decreases the need for human
sensory and mental requirements as well.
In order to design a control circuit, it should be divided
into several units or modules for its particular task or control
which first can be tested or implemented independently and
then combined together. The block diagram of PLC Based
Rheometer Control System is described in Figure 4.To
accomplish the PLC based control system, the design uses
Manuscript received Oct 15, 2011.
Khin Su Hlaing, Electronic Department, Mandalay Technological
University.,
([email protected]).
Mandalay,
Myanmar,
09-401554721
Kyaw Zin Latt, Electronic Department, Mandalay Technological
University.,, Mandalay, Myanmar, 09-444033279., (kyawzinlattsbo@
gmail.com).
LM35 Sensor
Heater
IR Sensor
Fig. 1.Block Diagram of the System
II. PROGRAMMABLE LOGIC CONTROLLER
A.Introduction of PLC
PLC is a solid state device. They are well-adapted to a
range of automation tasks .All control operations are done
using the PLC. The entire bottling process is automated by
feeding the necessary conditions into the PLC using ladder
logic. Ladder logic is one of the methods of programming a
PLC. Thus, depending on the logic developed the various
operations take place and the filling and capping of bottles
are done. PLC consists of an I/O unit, central processing unit,
and a memory unit. The input/output unit of the PLC acts as
an interface to the real world. Inputs from real work are given
to the input unit which is manipulated based on the
programming, and the results are given back to the real world
through the output unit of the PLC. All logic and control
operations, data transfer and data manipulation operations are
done by the central processing unit. The results and statuses
are stored in the memory of the PLC. PLC’s are used for a
wide range of applications especially in the field of control
and automation. Figure 2 shows the block diagram of PLC.
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012
D.Ladder Softwre Implementation
The AutoStation installation package issued by Invt
Auto-Control Technology Co., Ltd. (for short, Invt) is an
executable program. The main interfaces include 7 sections:
Menu, Tool bar, Project Manager Window, Instruction Tree
window, Information window, Status bar and Operation area.
Figure 4 shows the auto station main interface.
Fig. 2.Block Diagram of PLC
B.Ladder Programming algorithm
There are many types of programming languages in
Programmable Logic Controller, PLC. Languages are
typically fixed to Ladder Logic (LD), Sequential Function
Block (SFC), Function Block Diagram (FBD) and Structure
Text (ST). The common program language of PLC is ladder
diagram.
Programmable Logic Controller (PLC) is a specialized
computer used to control industrial machines and processes.
PLC has a CPU that is dedicated to run one program that
monitors different inputs and logically manipulates the
outputs for the desired control. Output/Input signals are DI
(Digital Input), AI (Analog Input), PI (Pulse Input), DO
(Digital Output), AO (Analog Output) and PO (Pulse
Output). There are four basic steps in the operation of all
PLCs: which continually take place in a repeating loop: Input
Scan, Program Scan, Output Scan and Housekeeping. Thus
PLC plays an important role in the feature industry.
C .Ladder Logic
Ladder diagram is an automatic control diagram language
that developed during World War II. Ladder logic is the
primary programming language of programmable logic
controllers. Since the PLC was developed to replace relay
logic control systems, it was only natural that the initial
language closely resembles the diagrams used to document
the relay logic. By using this approach, the engineers and
technicians using the early PLCs did not need retraining to
understand the program. To introduce ladder logic
programming simple switch circuits are converted to relay
logic and then to PLC ladder logic. Any control task
modifications are done by changing the program. This is why
the use of the PLC is preferred to the traditional hard wired
circuits in industrial controls. PLC architecture is shown in
figure 3.
Fig. 3. PLC Architecture
Fig. 4. Auto Station Main Interface
III. HARDWARE DESIGN FOR THE SYSTEM
This design can be divided into several units or modules.
They are sensor unit, processing unit and power unit. There
are some devices and components used in the in the design to
implement each unit. These devices used in this system are as
follows;
 Power Supply Unit
 IR Sensor
 IVC1 1006MAT PLC controller
 H-bridge DC motor
 LM35 Temperature Sensor
A. Power Supply Unit
The DC power supply unit is vital component in modern
electronic devices as they need a wide range of DC voltages
for their operations. The purpose of a power supply is to
provide the required amount of power specified voltage from
primary source.
B. IR Sensor
In this system, TSOP 1738 IR sensor is used to control
the DC motor. The pin diagram of the IR sensor is shown
in figure 5. The features of IR sensor are:
 Photo detector and preamplifier in one package
 Internal filter for PCM frequency
 Improved shielding against electrical field
disturbance
 TTL and CMOS compatibility
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012





Output active low
Low power consumption
High immunity against ambient light
Continuous data transmission possible (1200 bit/s)
Suitable burst length .10 cycles/burst
Fig. 5. Pin Diagram of IR Sensor
C. LM35 Temperature Sensor
LM35 sensor is used to sense the temperature from the
heater. LM35 temperature sensor is shown in figure 6.
The features of LM35 sensor are;
 A precision IC temperature sensor
 Calibrated directly in degree Celsius
 Sensitivity 10mV/ ˚C
 0.5˚C accuracy (at +25 ˚C )
 Rated for full -55˚C to +150 ˚C
E. H-bridge DC Motor
Bidirectional control of a DC motor requires a circuit
called an H-bridge. The H-bridge, named for its schematic
appearance, is able to move current in either direction
through the motor winding. H-bridge topology was chosen in
this system. An H-Bridge configuration using BJTs is shown
in Fig 8. It is called an “H-Bridge”, because it looks like an H
letter. An H-bridge is an electronic circuit which enables
electric motors to be run forward or backward action. It is
available as integrated circuits or can be built from separate
components for specific design. In this system, the DC motor
with H-bridge driver circuit is used to open and close the
shutter and to press the rubber. The motor can provide for
both directions: clockwise (CW) direction and counter
clockwise (CCW) direction. This circuit uses four transistors
for forward and reverse directions. Its operation is as follows.
To rotate the DC motor four transistors are used. When the
transistor Q1 and Q4 are ON and the other transistors are
OFF, a positive voltage will be applied across the motor and
the motor will rotate clockwise direction. When the transistor
Q2 and Q3 are ON and the other transistors are OFF, the
voltage across the motor will be negative, allowing counter
clockwise operation of the motor. In DC motor, clockwise
direction for Up-condition and counter clockwise direction is
for Down-condition.
Vcc
A
Q1
Q3
D
M
B
Q2
Fig. 6. LM35 Sensor
Q4
C
GND
D. Features of IVC1 1006MAT PLC Controller
The programmable controller PLC that is used in this
research is IVC1-1006MAT. It has 10 inputs and 06 outputs.
As shown in Figure 7, PORT0 and PORT1 are for
communication. PORT0 is RS232, and use socket Mini
DIN8, while PORT1 is RS485 or RS232. The bus socket is
for connecting extension modules. The mode selector switch
can be set to ON or OFF.
Fig. 7. Structure of IVC1 series basic module
Fig. 8.H-bridge DC-motor Circuit
IV. SIMULATION RESULT OF THE SYSTEM
The simulation of rheometer is carried out with the Auto
Station in order to know the performance of the controller.
AutoStation software platform is used to perform the
experiment. The PLC for experiment is equipped
withIVC1-1006MAT programmable logic controller. Figure
9 shows the connection of programming cable and figure
10shows the ladder diagram of the system. Circuit overview
of the system is shown in figure 11.
In this system, the ladder program must be run in the PLC
controller by downloading ladder software.
Basic requirements are also needed;
 PLC
 Programming Device ( personal computer )
 Programming Software and

Connector Cable
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012
Fig. 9. Connection of programming cable
Fig. 11.Circuit Overview of The System
V. SUMMARY
The software implementation of the rheometer control
system is described. The desired programming software is
used in autostation for PLC controller. This system is used in
rubber-related manufacturing industries. The rheometer is
used to measure the viscosity of the rubber. This machine is
very suitable for the industries and laboratory. The IR sensor
and LM35 temperature sensor are reliable parts of the system
for compared to other.
VI. CONCLUSION
The operation of rheometer is successfully done with the
use of PLC. Utilizing the IR sensors and LM35 sensor, PLC
controls the total rheometer. The PLC offers a compromise
between advance control techniques and present day
technology. The PLC reduces the operator intervention. A
rheometer is successfully developed by using PLC.
Rheometer can also be used for other types of materials. By
this investigation, the quality of rubber/polymer materials
such that the product that is produced complies with
international standards can be test.
REFERENCES
Fig. 10. Ladder Diagram of Rheometer
Table 1.List of Symbol meaning from Ladder Diagram
Input
Output
X0 = System Start
Y0 = Heater ON
X1 = System Stop
Y1 = Shutter motor forward
direction
X2 = Sensor 1
Y2 = Torque motor forward
[1] Carlos A Smith and Armando B Corripio, “Principles and Practices of
Automatic Process Control”, John Wiley & Sons July 2005.
[2] A.A. Collyer and D.W. Clegg, “Rheological Measurement, Second
Edition”, Chapman and Hall, 1998.
[3] Krishan Kant, “Computer-based Industrial Control”, prentice hall of
India Pvt.Ltd, 2004.
[4] W.Bolton, “Programmable Logic Controllers, Fourth Edition”.
[5] International Journal of Mechanical and Production Engineering, ISSN:
2320-2092, Volume1, Issue- 4, Oct-2013
[6] International Journal of Emerging Technology and Advanced
Engineering Website: www.ijetae.com (ISSN 2250-2459, Volume 2,
Issue 8, August 2012)
direction
X3 = Temperature Sensor
Y3 = Shutter motor reverse direction
X4 = Sensor 2
Y4 = Torque motor reverse direction
X5 = Sensor 3
Y5 = LED
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